Is it a coincidence that the exterior of the walnut resembles the human brain? Apparently not, as various studies prove that the consumption of walnuts exerts a thoroughly positive impact on brain activity. Thus, within the parameters of dementia research carried out in 2014, a study was carried out on mice with a genetic predisposition to Alzheimer's disease. Their diet was supplemented with walnuts in the hope of ascertaining effects on memory and learning behaviour. They received fodder incorporating 6% walnuts, with a second group of mice receiving 9% walnuts. Converted into human nutrition, this would correspond to a daily portion of walnuts weighing 28 g and 42.5 g, respectively. Improvements in memory capability and learning capacity, during states of anxiety and respective to motor developments were in evidence in both groups compared with mice with the Alzheimer gene that had not consumed walnuts. Since both groups behaved in exactly the same manner as healthy mice, the research findings suggest that supplementing the diet with walnuts can reduce the risk of Alzheimer's disease and delay its onset and progression.
A further U.S. study with 64 students aged between 18 and 25 investigated whether walnuts can promote cognitive performance. To this end, two groups each consumed three slices of banana bread for a period of 16 weeks. Consecutively over eight weeks, the bread given to one group was enriched with walnuts, and after a six-week break, so was the bread given to the other group. The subjects were also required to correctly map various statements to incomplete narratives. The students consuming banana-and-walnut bread were 11.2% better at this than subjects refraining from walnut consumption. The walnut bread exerted no effects on memory and mood, but this test demonstrates improvements in deductive thinking. Walnut contain numerous valuable ingredients. Along with a series of antioxidants that possess anti-inflammatory properties and protect the brain cells, they provide proteins, fibre, vitamins and minerals and, above all, an abundance of alpha-linoleic acid. This is needed in the brain so as to ensure correct and rapid signal transmission. Accordingly, supplementing the diet with walnuts is recommended for maintaining cognitive performance.
Chauhan, A. et al.: Dietary Supplementation of Walnuts improves Memory Deficits and Learning Skills in Transgenic Mouse Model of Alzheimer’s Disease. Journal of Alzheimer’s Disease 42, 2014, (1397–1405)
Pribis, P. et al.: Effects of walnut consumption on cognitive performance in young adults. British Journal of Nutrition, 2012, (1393–1401)